Film holder



Jan. 6, 1959 c. G. PADGIETT 2,867,161

FILM HOLDER Filed Feb. 14, 1956 NVENTmZZ g qy w 2,867, l 61 PatentedJan. 6, 1959 FELM HQlLDER (Iiarence Gary Padgett, Glenview, Ill.Application February 14, 1956, Serial No. 565,363

4 Claims. (Cl. 95-100) This invention relates generally to film holdingdevices and particularly to an improved holder for dental X-ray film, orthe like.

Dental ofiices are generally provided with dental X-ray machines inorder that X-ray photographs may be readily made for diagnosticpurposes. X-ray pictures taken by these machines are normally developedon the premises by the dentist or his assistants, and the processemployed for their development is similar to that normally employed indeveloping photographs, in that the X-ray film is first immersed in adeveloping solution, washed, immersed in a fixing solution, washed andfinally dried, as is well understood in the art. A number of types ofdental X-ray film holders, for supporting the film during thedevelopment process, have been utilized, and those devices heretoforefurnished the profession have often been found to be of inadequatecapacity and to require undue manipulation for loading and unloading offilm.

It is, therefore, a primary object of this invention to provide a novelX-ray film holder.

A further object is to provide a novel X-ray film holder of largecapacity yet which is compact.

Another object is to provide a novel film holder that is provided withmeans for facilitating the loading'and unloading thereof.

A further object is to provide a novel film holder that will notphysically harm the image on the film supported thereby.

Other objects and advantages of the invention will become apparent fromthe subsequent description taken in conjunction with the accompanyingdrawing wherein:

Fig. l is a front elevational View of a specific embodiment of the filmholder;

Fig. 2 is side elevational view of the device shown in Fig. 1;

Fig. 3 is a front elevational view on an enlarged scale of a portion ofthe device shown in Fig. 1, illustrating the relationship of its partsduring loading and after being loaded with film; and

Fig. 4 is an end elevational view ofa portion of the device shown inFig. 3 as seen along line 4-4 of Fig. 3.

In general the objects of the invention are accomplished by providing arack which is adapted to support a large number of sheets of X-ray film,or the like, by utilizing one or more tension springs to grip the edgesof the sheets. The springs are the primary film holding elements and areprovided with means for releasably securing them in extended conditionfor facilitating the load- .ing of the film. After the device has beenloaded the springs are released to clamp or tightly grip the film.

Referring to the drawing, the device comprises a generally rectangularrack 11, which is the main supporting member of the device. The rack isshown as having a vertical dimension greater than its width in thisinstance, so that it may be accommodated in the developing and Washingtanks that are currently being used in a number of dental oilices. It isshown having a pair of vertical side rails 12 and 13, a top rail 14 anda bottom rail 16. The corners of the frame are shown rounded, as at 17,for reducing their tendency to catch on objects and thus facilitatingthe insertion of the device into developing tanks. In the presentinstance, the frame 11 is shown as being made of bar stock having asquare cross section.

Inasmuch as the film must be dried after being developed, fixed andwashed, the'device is provided with a means for suspending it. In thisembodiment the sus- Pension means comprises a sheet metal hook 18rigidly secured around top rail 14 and which is adapted to be hookedover a suitable projection to suspend the device during drying. Hook 18also provides a handy means for supporting the device while it is beingloaded and unloaded.

This device relies upon the gripping forces existing between adjacentturns of a coil tension spring for supporting Sheets of film, or thelike. In this embodiment a plurality of identical coil tension springs19 are disposed parallel to each other and transversely between siderails 12 and 13 of the frame. Springs 19 areshown spaced one from theother sufiiciently far apart so that sheets of film 21 may be interposededgewise between adjacent turns of a spring 19 and transversely betweenit and an adjacent spring 19, without touching that adjacent spring, asbest seen in Figs. 1 and 3. Springs 19 when unextended are shorter thanthe distance between side rails 12 and 13. 'It is thus seen that when aspring 19 is extended to bridge the space between rails 12 and 13, itsadjacent turns are slightly spaced from each other, to facilitate theedgewise insertion of a sheet 21 therebetween. In the preferredembodiment, the spring is dimensioned relative to the distance betweenrails 12 and 13 so that it can be stretched only sufficiently to permitinsertion of a sheet 21 but will still grip the sheet,

i. e. the spaces between adjacent turns, when the coil is stretchedbetween the rails, are normally just slightly leSs than the thickness ofthe film to be inserted, as shown in the top portion of Fig. 3. Hence, asheet 21 may be easily inserted between the adjacent turns, but enoughforce remains between the sheet and the adjacent turns to retain thesheet in place until forcibly removed. The advantages of thisarrangement are several. coil spring affords a means of sheets of filmat any one being spaced from adjacent sheets by one or more turns of thecoil therebetween, the coil frictionally grips the edge of the sheetwithout punching holes in it or other- The for holding a large numbertime with each sheet of film wise 'mutilating it, and during loading andunloading,

even when the spring is extended the sheets of film are frictionallyretained in place until either firmly gripped by the spring or forciblyremoved.

Each spring 19 is in this embodiment supported by and telescoped' overan elongated rod 22. Rods 22 are carried by and extend between rails 12and 13 and in this instance rods 22 are welded to rails 12 and 13. Rods22 serve not only assupports for the springs 19 and as stiifeners forframe 11 but also, by virtue of their being disposed within the springs,rods 22 act as guards for preventing undue insertion of sheets 21 intothe spaces between adjacent turns of springs 19. Inserting of film tothe extent that more than its mere border extends between the adjacentturns and within the coil possibly would prevent proper development ofpart of the image. Helically wound coils, inherently prevent a sheet ofmaterial from being completely inserted through the coil, and byutilizing a coil having a diameter less than the border width of thefilm, such undue insertion of the sheet would be avoided but in thatcase only a very small area of the film would be gripped. Where greatergripping between coil and sheet is desired than can be obtained by asmall diameter spring, the use of rods 22 in conjunction with telescopedsprings 19 permits the use of larger diameter springs havingcorrespondingly greater gripping area, without sacrificing limitation ofthe depth to which the sheet may be inserted. Thus, rods 22' provide apractical means for eliminating a source of damage to the image on afilm by limiting the gripping by spring i9to the border of sheet 21. Theelimination of this chance of damage thus simplifies loading by anoperator.

To facilitate the extending of spring 19 one end of each is anchored infixed position relative to the frame while the other end is free. Thuseach of the springs 19 in this embodiment has one end 23 anchored toframe 11 by welding it along with rod 22 to side rail 13. To extend thespring and releasable secure it in extended condition, the end oppositefixed end 23 is bent to form a-hook 24 which terminates in a suitablehandle portion 26. A hook-receiving slot 27 is formed adjacent thejuncture between rod 22 and side rail 12, and after extending spring 19longitudinally along rod 22, hook 24 may be slightly turned about theaxis of the spring and engaged in the slot 27. The tension of spring 19exerted through hook 24 thus releasably secures the spring in extendedcondition for loading. Upon disengagement of. hook 24. after loading,and on release of the spring, the hook 24 swings out of alignment withthe slot 27 and the spring shortens to move the hook 24 along the rod.Thus the tension in the spring tightly clamps or grips the edge ofsheets 21, 7

as is shown in Fig. 1 and the lower portion of Fig. 3.

From the foregoing it is seen that this device affords an improved meansfor supporting a plurality of sheets of X-ray film, or the like, that itis adapted to support a large number of sheets of film, is easilymanipulated to facilitate loading and unloading and will frictionallysup port the film Without possibilityof harm to the image thereon.

Although the invention has been described in connection with a certainspecific structural embodiment of the invention, it is to be understoodthat various modifications and alternative structures maybe resorted towithout departing from the scope of the invention as defined in theappended claims.

I claim: 7

1. A device of the character described comprising a generallyrectangular frame having a means for suspending said frame in a fluid,an elongated cross member extending between and carried by oppositesides of said frame and having a slot in one end, and an elongatedcoiled wire tension spring disposed telescoped over said cross memberand having one end permanently fixed relative to said frame and itsother end free, said free end having means for longitudinally extendingsaid spring along said cross member, said last-mentioned meanscomprising a hook formed from the wire of the spring, said hook beingrotatable about the axis of the spring and thereby movable into saidslot for releasably holding said spring in extended condition forholding the adjacent turns of said spring spaced one from another foreasy insertion of an edge of a sheet of photographic film material orthe like therebetween, said spring being adapted to support a pluralityof sheets of such material by gripping the edges thereof between therespective turns upon release of said holding-means.

2. A device of the character described comprising a frame, and anelongated coiled tension spring bent at one end to provide a hook, saidframe having a means for suspending the device in a fluid, a springsupporting cross member having a hook receiving slot adjacent one end ofsaid cross member, said spring being disposed around a portion of saidcross member and having the end opposite said hook permanently securedto said frame,

' said spring having a normal length requiring longitudinal extension ofsaid spring to engage said hook with said slot, said hook uponengagement with said slot releasably holding said spring in extendedcondition for holding the adjacent turns of said spring spaced one fromanother for easy insertion of an edge of a sheet of photographic filmmaterial or the like therebetween, and said spring being adapted tosupport a plurality of sheets of such material by gripping the edgesthereof between the respective turns upon release of said hook.

3. A device of the character described comprising a generallyrectangular frame, and an elongated coiled tension spring having one endbent to form a hook extending crosswise of the spring and terminating ina handle portion for extending said spring, said frame having means forsuspending the device in a fluid, a spring supporting cross rod having ahook receiving slot adjacent one end of said cross rod, said springbeing disposed around a portion of said cross member and having the endopposite said hook permanently secured to said frame, said spring havinga normal length requiring longitudinal extension of said spring toengage said hook with said slot, said hook being engageable with saidslot for releasably holding said spring in extended condition forholding the adjacent turns of said spring spaced one from another foreasy insertion of an edge of a sheet of photographic film material orthe like therebetween, and said spring being adapted to support aplurality of sheets of such material by gripping the edges thereofbetween the respective turns upon release of said hook.

4. A device of the character described, comprising a frame including across member, a coiled spring mounted on said cross member and securedat one end to said cross member at one side of said frame, the other endof said spring being formed into a hook and releasably engageable at theopposite side of said frame with said cross member to hold the springextended for insertion ofan edge of photographic film material or thelike between adjacent turns of the spring, said spring being solidlywound whereby the turns tend to, abut each. other when the spring isreleased and thereby firmly grip'said material, said cross memberlimiting said spring to a predetermined extended length such that thespacing between adjacent turns is slightly less than the thickness ofsaid material whereby the material is frictionally held by the turnswhen the spring is extended.

References Cited in the file of this patent UNITED STATES PATENTS495,102 Reid Apr. 11, 1893 1,205,747 Kawate Nov. 21, 1916 1,362,136Plante Dec. 14, 1920 1,466,339 Plante Aug. 28, 1923 2,522,416 WeiskoifSept. 12, 1950

